Gas–liquid nucleation of nonideal binary mixtures. I. A density functional study

The binary gas–liquid nucleation of model Lennard-Jones mixtures is studied using density functional methods. It is shown that the ordinary ‘‘Ar’’–‘‘Kr’’ mixture shows stronger nonclassical nucleation behavior than previously thought. A more nonideal mixture is defined by modifying the usual mixing rules of the Lennard-Jones parameters. This fluid exhibits significantly stronger surface activity than the ordinary mixture. As with water/alcohol systems, classical nucleation theory produces nonphysical predictions for the nucleation of the surface active mixture. On the other hand, the predictions of the density functional theory are thermodynamically consistent.